Hi guys

Brand new here and I need so help. Recently my 05 coupe overheated due to the thermostat sticking. It was replaced, ran fine. A few days later I noticed the temp climbing while on the hwy, brought it back and the proceeded to bleed the line again. Ran fine. Now it's hit and miss, when I'm on the hwy doing 80mph at 3000rpm the temp starts rising. When the rpm's drop the temp will drop. Stop and go traffic and city driving it runs fine. Runs fine on the hwy until i hit about the 20 mile mark at around 80mph. A/C and heater work as they should. Also fans are working. The lower splash gaurd is not on but it never has been, and the car is stock. Help!

 

What did you replace it with? Is the thermostat the correct one?

Have you followed the troubleshooting steps in the FSM?

http://www.nicoclub.com/FSM/G35/Coupe/2005/co.pdf

Did you perform a pressure test?
Replace the radiator cap
Perhaps you have a clogged radiator or a defective water pump?

Put it back on. Not sure how that effects air flow

Telcoman

 

My mechanic replaced the thermostat, not sure which brand he put in, he got the air out the line. The radiator was flushed twice. They did all the trouble shooting. The temp on the two hoses felt fine. A/c temp was normal. Radiator cap was also replaced. Oil looks normal. Car runs fine.

 

Did they check/clean the front of the radiator to see if there any leave or junk? Could be a partially clogged radiator or collapsing hose.

 

Yes they checked those things.

 

Trapped air. Or you are reingesting air because not enough coolant - check overflow tank and make sure it is not empty when cold.

 

I did and the levels are normal.

 

did you ever find the cause of this issue? i am currently experiencing it myself and cannot figure it out.

 

Pressure test your coolant system to find why it's not holding pressure.